1. Field
This disclosure relates in general to radio location systems and, more specifically, but not by way of limitation, to transferring location related trust information between Access Point and Wide Area Networks.
2. Information
There is an ever growing desire to know the geographic position of various mobile devices. For example, some cellular phone operators may need to comply with requirements to locate handsets for emergency purposes. Once position is known, emergency personnel can be dispatched to aid resolving the emergency. Knowing geographic location serves many other purposes such as location-based advertising, child supervision, automated parolee supervision, reverse 911, fleet vehicle tracking, etc.
Currently, there are many ways to estimate a position of a mobile device on a network. For example, Global Navigation Satellite System (GNSS) solutions on a mobile device may provide position estimates that are most accurate when the mobile device is located in outdoor and open space environments. In another example, Wide Area Networks (WAN) base stations and Access Point (AP) networks (e.g., using WiFi, CDMA, WCDMA, LTE or other WAN Femtocells, or Bluetooth) can be used to estimate the position of a mobile device.
In general, AP based positioning is dependent on the integrity of information stored in an Almanac. In an embodiment, an almanac can be a database including a Service Set Identification (SSID), Media Access Control (MAC), or other appropriate address identifier, and position information associated with a wireless access point. The term access point can be a short range wire transceiver including WiFi access pints, Bluetooth transceivers, femtocells, and other short range wireless transceivers. The integrity of an almanac can be degraded due to the ease with which an owner of a wireless access point can move the hardware between locations without registering a new location for the AP. The integrity of the almanac may also be diminished by incorrect signal measurement, corrupt data, and other system failures.
In some areas of the world a stable AP almanac can be established, but the integrity of the location information in a WAN almanac may be lacking. In this case, access point generated position estimates can be used to verify the WAN base station positions.